Casting apparatus



MT WAGNER CASTING APPARATUS Nov. 25, 1958 2 SheetsPSheet 1 Filed March12, 1956 CASTING APPARATUS Matthew Wagner, Burbank, Calif. ApplicafionMarch 12, 1956, Serial No. 570,883

1 Claim. (Cl. 22-151) This invention relates generally to a castingapparatus and relates more particularly to a casting apparatus formanufacturing large metallic rings employed about the upper end of seweropenings. Such rings are commonly referred to as sewer rings and providea finishing means for the tops of manholes, with portions thereof setflush with street paving surfaces and providing a receptacle for amanhole cover.

I-Ieretofore, sewer rings and other large types of castings have beenmanufactured using sand type casting processes requiring a considerableamount of time, effort and expense in the forming of the sand mold.Additionaliy, sand type molds provide a rough surface casting and cannaturally only be used once. The time necessary to construct the mold,using suitable patterns and to allow for suitable cooling time formolten metal placed therein required the maintenance of foundrymen andconsiderable foundry space in order that production quantities ofcastings may be produced. In other words, several individual operatorshoused in a large foundry floor area have been required heretofore.

In addition, sand type castings develop a considerable amount ofporosity that produces castings of inferior quality.

It is, accordingly, one important object of the present invention toprovide a casting apparatus for manufacturing such castings as sewerrings, for example.

It is another important object of the present invention to provide anapparatus for manufacturing relatively large castings, wherein apermanent mold is provided, to gether with means for operating thismold.

A further object of this invention is to provide a permanent moldingapparatus for manufacturing relatively large castings, without the useof expendable cores and the like.

A still further important object of this invention is to provide apermanent molding apparatus for producing relatively large castings insuch a manner as to insure w porosity of the finished casting, reducethe need for expensive machining of the casting and insure qualityproducts.

Still another object of the invention is to provide a permanent moldingapparatus that is rapid and efficient in use, reliable in operation andwith which casting time, manpower requirements and floor spacenecessities may be reduced to an absolute minimum commensurate withproduction requirements.

Other and further important objects of this invention Will becomeapparent from the disclosures in the following detailed specification,appended claim and accompanying drawings forming a part hereof andwherein:

Figure 1 is a top plan View of the present casting apparatus;

Fig. 2 is an elevational view, partially in section, and takensubstantially as indicated by line 2-2, Fig. 1;

Fig. 3 is a partially sectional view similar to Fig. 2, showing parts indifferent positions;

Fig. 4 is a fragmentary sectional view through the pour- 2,861,306Patented Nov. 25, 1958 ing basin, as taken substantially as indicated byline 4--4, Fig. 1; and

Fig. 5 is a schematic diagram illustrating operating controls for usewith the present apparatus.

With reference to the drawings, the present apparatus includes agenerally annular base 10, having a centrally disposed, slightlyvertically tapered opening or aperture 11 therein. The base 10 may besupported in any suitable manner, such as for example, as byappropriate'legs 13. The base 10 also has radially disposed bracketportions 14 that extend from the outer periphery thereof and are formedintegrally with the base for a purpose to be hereinafter more fullydescribed.

The base 10 serves to support a movable segmented cope indicatedgenerally at 15. The cope 15 includes a plurality of arcuate segments 16that are radially slidably disposed thereon by means of outwardlyextending tab portions 17 formed integrally with each cope segment 16and cooperably disposed in radially disposed slots 18 in an uppersurface 19 of the base 10. The slots or grooves 18 are tapered relativeto a radian of the segmented sections of the cope in order to permitfree radial movement of the cope segments and slight misalignmentthereof when the tabs 17 are radially outer ends of the slots. The uppersurface 19 of the base 10 is planar to provide for easy movement of thecope segment 16, while still maintaining precise alignment thereof. Theinner annular edges of the cope segments 16 have their upper surfacesprovided with annular inwardly directed recess 20, the outer annularedge of which is undercut as at 21. An inner annular edge surface 22 ofthe cope segments is spaced radially outwardly from a continuation ofthe annular opening 11 in the base and is slightly conical.

With reference primarily to Fig. 2, the base 10 is provided with anannular groove 23, adjacent the upper peripheral edge of the opening 11that is counterbored' as at 24. The upper edge of the annular groove 23normally communicates with a lower edge surface 25 of the cope segments.

The cope segments 16 have circumferential abutting surfaces 25, aradially inward portion thereof being circumferentially relieved as at27 to provide a radial space between portions of the circumferentialends of the cope segments.

With reference primarily to Figs. 1 and 2, a core member 28 ispositioned normally within the opening 11 in the base 10. The core 28 isgenerally annular and provided with an outer annular surface 30 that isslightly tapered in conformity to the conical taper of the opening 11 inthe base 10. The upper surface 31 of the' core 28 normally extendsslightly above an upper surface 32 of the cope segments 16. A lowersurface 33 of the core 28 is adapted also to extend slightly below alower surface 34 of the base 10.

It may thus be seen that when the core 28 is positioned as shown inFigs. 1 and 2, a space or cavity is defined between the core 28, thebase 10 and the cope segments 16, this space being provided by thegroove 20, radially outwardly spaced cope segment surfaces 22, thegroove 23 and counterbore 24 in the base 10 and an outer surface 30 ofthe core 28. Additionally, the spaces defined between spacedcircumferential ends 27 of the cope segments also communicate with thespace defined between the core and the segments.

With reference primarily to Figs. 1 and 4, a pouring basin 35 isattached to an outer peripheral surface of one of the cope segments 16and has upwardly extending side portions 36 that extend over the uppersurface 32 of the cope segment. The pouring basin 35 is arranged with anopen mouth ferentially with respect to the annular groove 20 in the 37that is directed generally circum-' .from the upper position.

'3 cope segments 16, with which the mouth of the pouring basincommunicates.

Thus, molten metal poured into the pouring basin 35 will be deliveredina circumferentially directed fashion to the groove and will travel aboutthis groove within the confines of the outer peripheral edge of thegroove 20 and undercut 21, also running outwardly into the space definedbetween the cope edge 22 and the core outer surface and into the groove23 and counterbore 24 in thebase. The circumferential directionalmovement of the molten metal within the confines described hereinbeforeserves evenly to distribute the molten metal about the core 28 and toprevent the formation of any hot spots or other local heating withregard to the core or other components of the apparatus. The. moltenmetal also extends into the radial space defined between the copesegment ends 27. Thus a sewerring indicated at R is molded within theconfines of the base, cope segments and core, with the upper surface ofthe ring R being unconfined and accordingly slightly roughened.

Each of the cope segments 16 has attached thereto a piston rod whichextend radially outwardly therefrom to hydraulic cylinders 41, each ofwhich are supported on the radially outwardly extending tabs 14 from thebase 10. The core 28 is supported normally in a position within the base10 by means of a piston rod 42 which extends outwardly from a centralbottom area thereof, to a hydraulic cylinder 43. The hydraulic cylinder43 may be carried by a platform 44 connected with the legs 13 of thebase structure 10.

After molten metal is poured into the pouring basin 35 and thereafterinto the space defined between the core, cope segments and base, slightsolidification thereof occurs as this metal cools and the core 28 iswithdrawn from its normal position, as shown in Fig. 2, to a lowerposition as shown in Fig. 3. The beveled outer surface 30 of the core 28and the conical beveled surface of the opening 11 in the base serve topermit easy removal of the core Immediately thereafter, the various copesegments 16 are moved radially outwardly from the positions shown inFig. 2 to the positions shown in Fig. 3, thus to' expose the sewer ring-R in such a manner as to permit removal thereof from the castingapparatus. Movement of the core 28 and the cope segments 16 may beaccomplished by any suitable operative structure, such as for example,the hydraulic cylinders 41 and 43 that may be controlled by means of thehydraulic system set forth in Fig. 5.

As shown in the diagrammatic illustration of the hydraulic system inFig. 5, hydraulic fluid is delivered from a sump to a pump'51 by meansof a conduit 52 and from the pump 51 by way of a conduit 53 to a Yconduit 54 and thereafter to rotary valves 55 and 56. From the rotaryvalve 55, hydraulic fluid is delivered by way of a conduit 57 to oneside of the cylinder 43, to move the piston rod 42 and the core attachedthereto in a downward direction. Return fluid from the cylinder 43 isconducted by way of a conduit 58 through the rotary valve 55 and by wayof a conduit 60 to the sump 50. Fluid delivered to the rotary valve 56by way of the Y conduit 54 is delivered through a conduit 61 to a pairof branch conduits 62 and 63 and thereafter to one side of each of thecylinders 41, to move the piston rods 40 thereof and the cope segments16 that are attached thereto in a radially outward direction. Returnfluid from the cylinders 41 is conducted by way of branch conduits 64and 65 to a conduit 66, to the rotary valve 56 and by way of a conduit67 to the conduit 60 and thereafter back to the sump 50. When the rotaryvalves 55 and 56are moved to the position shown by the dotted linestherein, the direction of the fluid to both the cylinder .43 andcylinder 41 is reversed whereby to move the pistons and rods of thesecylinders in opposite directions, again to position the cope segmentsand the Core as shown in Fig. 2. The pouring movement, downward movementof the core 28 and radially outward movement of the cope segments 16,together with the return of the core in an upward direction and radiallyinward movement of the cope segments comprises one complete cycle of thepresent apparatus, with the completed sewer ring R being removed duringthe open time of the core and cope.

Each of the cope segments 16 are provided with semicircular passages 70therein, to which conduit connections 71 and 72 are connected.Additionally, the core 28 is provided with an internal cavity 73, havinga centrally disposed partition 74, the cavity 73 having conduits 7S and76 extending respectively thereto and therefrom. The base 10 is alsoprovided with an annular passage 77 which is spaced radially outwardlyfrom the opening 11 therein. This passage structure 77 has a conduit 78extending thereto and the conduit 80 extending therefrom. The page 70 inthe cope segments 16, the cavtiy 73 and thec ore 28 and the passage 77in the base 10 serve to provide means for circulating a cooling fluidtherein for controlling the temperature of these components when heatedby molten metal poured therebctween. For this purpose, fluid iscirculated from a sump 81, through a pump 82 and by way of conduits 82and 83 to the conduits 71, 75 and 78. Return fluid from the conduits 72,76 and 80 is returned by means of conduits 84 and 85 to the sump 81.Each of the conduits 71, 72, 75 and 76 may have attached theretoflexible lines in order to enable the necessary movement of both thecore 28 and cope segments 16.

It may thus be seen that the present apparatus may be cycled asdescribed hereinbefore in such a manner as rapidly to produce precisioncasting parts, with the base, cope segments and core being made from anysuitable metallic material having a melting point either at or somewhathigher than the melting point of the molten material to be pouredtherein. By withdrawing the various confining structures from themolding, easy and rapid removal of the sewer ring may be accomplishedwithout the necessity for utilizing expendable cores or like structures.Additionally, it is to be noted that relatively small floor area isrequired for maintaining high production of the sewer rings.

Having thus described the invention and the present embodiment thereof,it is desired to emphasize the fact that many modifications may beresorted to in a manner limited only by a just interpretation of thefollowing claim.

I claim:

A permanent molding apparatus for sewer rings comprising, incombination: a generally annular base structure having a centrallydisposed aperture therein; a generally cylindrical core movably disposedthrough said aperture, said core having an upper end; a segmented copeslidably disposed on said base structure and positioned normally tosurround a portion of said core in spaced relationship thereto wherebyto define an annular cavity therebetween, said core and said aperturehaving complementary generally conically tapered mating surfaces,segments of said cope being arcuate and having upper surfaces normallydisposed vertically below said upper end of said core, said surfacedefining an unconfinedv open face molding surface; an additional cavityformed in said base structure and communicating with said firstmentioned cavity; tapered radial groove means on said base structure forguiding said cope segments for radial movement thereof on said basestructure and relative to said core, said core and said cope beingangularly stationary relative to said base structure; a plurality offirst hydraulic cylinders positioned on said base structure, each copesegment being operatively directly connected with one of said cylinders;a second hydraulic cylinder mounted on said base structure and connectedwith said core; means for simultaneously actuating said first hydrauliccylinders whereby to effect radial movement of said cope segmentsrelative to said core; means for actuating said second hydrauliccylinder to effect longitudinal movement of said core in said aperture,said movement of said cope segments and said core acting to open saidfirst mentioned cavity following disposition of molten metal thereinwhereby to permit removal of said sewer ring from said additionalcavity; a pouring basin carried by one of said cope segments, saidpouring basin having a molten metal discharge end positioned generallytangentially with respect to said annular cavity; and means forcirculating cooling fluid through said base structure, cope segments andsaid core.

References Cited in the file of this patent UNITED STATES PATENTS HallSept. 14, Edlund Aug. 10, Lehman May 8, Carlson May 26, Bushnell Jan.19, Brown Nov. 13, Wagner Nov. 20, Wagner Feb. 13, Kost Jan. 16, Bean eta1. Feb. 26,

